larger diameter in rear than front
08-08-2009, 04:47 PM
#1
I know corvettes and ferraris use a larger diameter wheel/tire in the rear than front. 18s in front and 19s in rear with same profile on each which means larger diameter on rear
what is the point of that?
what is the point of that?
08-08-2009, 05:33 PM
#2
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If your car has the torque to spin the larger diameter wheels the purpose is to go faster. Larger diameter means more distance traveled in one rotation.
08-08-2009, 08:34 PM
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Originally Posted by cleung' post='969803' date='Aug 8 2009, 09:33 PM
If your car has the torque to spin the larger diameter wheels the purpose is to go faster. Larger diameter means more distance traveled in one rotation.
08-08-2009, 08:38 PM
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Originally Posted by Speed_Force_E60' post='969956' date='Aug 8 2009, 09:34 PM
bigger wheels cover more surface area per rotation. However, im too confused as to why they use a smaller wheel up front?
Smaller wheels up front help steering and handling, it would take a lot longer to make turns if they had huge wheels up front. Same reason we use a staggered set up - wider rear wheels provide better grip for acceleration. The net effect of staggered setup means better braking into a turn and better acceleration out of one. It does produce more understeer but that is more manageable for normal drivers than oversteer - although that idea is also ruined by the fact that ALL race cars use a staggered setup so apparently race drivers prefer understeer.
08-08-2009, 09:42 PM
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Originally Posted by pjinca' post='969963' date='Aug 8 2009, 10:38 PM
Smaller wheels up front help steering and handling, it would take a lot longer to make turns if they had huge wheels up front. Same reason we use a staggered set up - wider rear wheels provide better grip for acceleration. The net effect of staggered setup means better braking into a turn and better acceleration out of one. It does produce more understeer but that is more manageable for normal drivers than oversteer - although that idea is also ruined by the fact that ALL race cars use a staggered setup so apparently race drivers prefer understeer.
08-08-2009, 09:46 PM
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Originally Posted by cleung' post='970003' date='Aug 8 2009, 10:42 PM
this is correct but the OP is asking about larger diameter not wider width.
I would think same thing, larger contact patch resulting in better handling and better acceleration. Smaller width and diameter tires up front help with turn in.
08-09-2009, 07:42 AM
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Originally Posted by pjinca' post='970007' date='Aug 8 2009, 11:46 PM
I would think same thing, larger contact patch resulting in better handling and better acceleration. Smaller width and diameter tires up front help with turn in.
08-09-2009, 08:22 AM
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Originally Posted by pjinca' post='969963' date='Aug 8 2009, 11:38 PM
Smaller wheels up front help steering and handling, it would take a lot longer to make turns if they had huge wheels up front. Same reason we use a staggered set up - wider rear wheels provide better grip for acceleration. The net effect of staggered setup means better braking into a turn and better acceleration out of one. It does produce more understeer but that is more manageable for normal drivers than oversteer - although that idea is also ruined by the fact that ALL race cars use a staggered setup so apparently race drivers prefer understeer.
08-10-2009, 01:19 AM
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Larger rear diameters are mostly to put the power down, as opposed to just spin the drive wheels outta control on launches.
On e60 you cannot successfully run a discrepancy between overall rolling diameters between front and rear wheels of more than a few millimeters - it will affect the differentials and throw error codes at the very least. Definitely has been proven to destroy the diffs in the Xi cars - not sure whether RWD cars have experienced similar problems.
Staggered setup provides additional oversteer. In e60 it is not a bad idea, since the car has a slight tendency to understeer initially - increasing the car's desire to rotate will make it more fun to drive and more nimble - not to mention, easier to drift. Similar effect can also be reached by installing some spacers in the rear, because it effectively widens the rear track, thus increasing the oversteer. Though a true staggered setup provides more control due to larger surface contact areas of the rear tires.
On e60 you cannot successfully run a discrepancy between overall rolling diameters between front and rear wheels of more than a few millimeters - it will affect the differentials and throw error codes at the very least. Definitely has been proven to destroy the diffs in the Xi cars - not sure whether RWD cars have experienced similar problems.
Staggered setup provides additional oversteer. In e60 it is not a bad idea, since the car has a slight tendency to understeer initially - increasing the car's desire to rotate will make it more fun to drive and more nimble - not to mention, easier to drift. Similar effect can also be reached by installing some spacers in the rear, because it effectively widens the rear track, thus increasing the oversteer. Though a true staggered setup provides more control due to larger surface contact areas of the rear tires.